In forming luminescent areas of organic EL devices of an organic EL display panel, it is necessary to prevent a display performance degradation in the vicinity of outermost edges of display area of the organic EL display panel. A film formation mask is used to form a film pattern of an organic layer containing a luminescent layer, in a manner such that the luminescent area formation sections can be covered. The film formation mask has a plurality of openings according to the film pattern, and false openings formed outside the area containing the openings but not useful in forming organic layer for forming luminescent areas. False openings are formed in positions corresponding to the outside of display area, and forms false patterns of an organic layer on the inner side of the adhesive area.